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EARNINGS PER SHARE AND STOCKHOLDERS' EQUITY - Restricted Stock Awards and Share Repurchases (Detail) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	1 Months Ended		3 Months Ended				12 Months Ended
	Feb. 28, 2019	Feb. 28, 2018	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Repurchases of common stock
Reduction of equity for retirement of repurchased shares							$ 68,832	$ 34,899	$ 12,893
Dividends
Cash dividends paid per common share			$ 0.25	$ 0.25	$ 0.25	$ 0.25	$ 1.00
Dividend declared per share	$ 0.30
Dividend payment date	Mar. 07, 2019
Restricted shares
Repurchases of common stock
Repurchased and retired shares							0.2	0.2	0.2
Weighted average market price of shares repurchased and retired (in dollars per share)							$ 51.86	$ 41.21	$ 22.74
RSUs
Repurchases of common stock
Repurchased and retired shares							0.0	0.3	0.0
Weighted average market price of shares repurchased and retired (in dollars per share)								$ 39.82
Share repurchase program 2016
Repurchases of common stock
Reduction of equity for retirement of repurchased shares									$ 9,200
Share repurchase program 2016 \| Common shares
Repurchases of common stock
Repurchased and retired shares									0.4
Weighted average market price of shares repurchased and retired (in dollars per share)									$ 23.11
Share repurchase program 2017
Repurchases of common stock
Reduction of equity for retirement of repurchased shares						$ 11,400		$ 16,000
Share repurchase program 2017 \| Common shares
Repurchases of common stock
Repurchased and retired shares						0.2		0.3
Weighted average market price of shares repurchased and retired (in dollars per share)						$ 46.77		$ 47.10
Share repurchase program 2018
Repurchases of common stock
Reduction of equity for retirement of repurchased shares							$ 45,600
Share repurchase program 2018 \| Common shares
Repurchases of common stock
Repurchased and retired shares							1.0
Weighted average market price of shares repurchased and retired (in dollars per share)							$ 45.37
Share repurchase program, period for repurchases		12 months
Authorized share repurchase capacity remaining			$ 4,400				$ 4,400
Share repurchase program 2018 \| Common shares \| Maximum
Repurchases of common stock
Repurchase authorization		$ 50,000
Share repurchase program 2019 \| Common shares
Repurchases of common stock
Share repurchase program, period for repurchases	12 months
Share repurchase program 2019 \| Common shares \| Maximum
Repurchases of common stock
Repurchase authorization	$ 50,000